PDF《(+)-Isomethoxystemofoline》

30 mL). The combined organic layers were washed with brine, dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by flash chromatography (EtOAc/PE = 1/4) to give cis-7 (5.61 g, yield: 70% from 10) and trans-7 (1.52 g, yield: 20% from 10). cis-7: colorless oil. [?]D

20 ?49.5 (c 1.0, CHCl3);

IR (film) vmax: 2953, 2929, 2857, 1697, 1454, 1421, 1376, 1255, 1098, 1027, 836,

778 cm-1 ;

1 H NMR (400 MHz, CDCl3) ? 0.02 (d, J = 2.5 Hz, 6H), 0.85 (s, 9H), 1.61 (td, J = 5.0, 13.7 Hz, 1H), 2.12 (s, 3H), 2.53 (td, J = 7.6, 13.7 Hz, 1H), 2.61 (dd, J = 9.8, 17.7 Hz, 1H), 3.........